I’m giving an update on this case so that this may be useful to someone in future.
My first issue was related to a 404/not found for mautic-form.js on a Wordpress contact page where a Mautic form is embedded via a standard [mauticform id=“4”] shortcode.
This was due to a misconfiguration on my mautic / configure panel where, under “site Url” I wrongly inputed my Matic installation folder, instead of the plain website domain where my Mautic instance was installed.
So, if you, like me, have installed your Mautic instance in your website subdirectory, under the Mautic/Configuration/siteUrl just indicate your site url, e.g. www.yourdomain.com.
This was indicated to me by @MxyzptlkFishStix so all credit and praise should go to him.
After resolving that issue, I had the very annoying issue of my Mautic form hanging on the “please wait” status, instead of proceeding to the scheduled action (e.g. show message, redirect, remain on form).
I tried a different set of solutions posted on the internet (this issue seems pretty common) and what resolved for me was to uninstall the “WP Mautic” plugin which I had installed on my Worpress instance vers. 4.7.4 via the Worpress Plugin repository, and downloaded and installed the one found on Github: https://github.com/mautic/mautic-wordpress
One obvious difference between the 2 versions of the “WP Mautic Plugin” is the embedding shortcode.
The embedding shortcode of the “WP Mautic” plugin downloaded from the Wordpress plugin repository was:
The one for the “Wp Mautic” plugin downloaded from Github is
[mautic type="form" id="2"]
The above does not make a lot of sense to me, but still this is what has been working on my use case.
I hope this will be useful for someone else in future.
Thank you for reading and special thanks to @MxyzptlkFishStix